JP2014046550A - Oil penetration/drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dry a wood until the moisture content of the wood becomes 10% or less, and to prevent an oil used for drying from penetrating into the core of the wood.SOLUTION: This device comprises: an oil tank filled with an oil such as a vegetable oil; a treatment kettle for storing a wood, having an inner part into which the oil is injected from the oil tank; a boiler for heating the oil in the treatment kettle gradually to lower the moisture content of wood to 10% or less, and heating-controlled so as to have a time and a temperature at which penetration of the oil does not reach the core of the wood but stops on the surface edge side; a radiator installed underwater, for allowing inflow of the heated oil to cool it; and a pump for returning the oil into the oil tank when its temperature is lowered to a prescribed temperature by the radiator.

Description

  The present invention relates to a vegetable oil permeation drying apparatus that can dry wood to a moisture content of 10% or less in the same kiln and at the same time allow oil such as vegetable oil to penetrate into the wood.

  Conventionally, as a device for drying wood, for example, in Japanese Patent No. 3396673, wood is stored in a heating device and filled with waste oil and heated for a certain period of time. In the meantime, a structure is disclosed in which the inside of the heating device is cleaned, the inside of the heating device is cleaned and then the replaced wood is returned and reheated, and air is injected and cooled after heating. In addition, it was necessary to put in and out twice, and it was necessary to clean the inside of the heating device before reheating the wood.

Japanese Patent No. 3396673

  The problem to be solved by the present invention is to provide an oil such as a vegetable oil used for drying and a method for drying the wood to a moisture content of 10% or less in the same treatment kiln.

In order to solve the above problems, in the invention of the oil permeation / drying device according to claim 1,
An oil tank filled with oil for drying and impregnating wood such as vegetable oil;
A processing kiln that stores wood and injects oil from the oil tank into the interior,
A boiler that is heated and controlled at a time and a temperature at which the oil in the treatment kettle is gradually heated so that the moisture content of the wood is 10% or less and the oil does not impregnate the core of the wood but only impregnation on the front edge side;
A radiator that flows and cools the heated oil in the treatment kiln from the treatment kettle through a pipeline;
A pump for returning to the oil tank when the oil is reduced to a predetermined temperature by the radiator;
It is characterized by comprising an automatic control device for controlling the temperature of oil in the treatment kiln by heating control of a boiler.
In the invention of claim 2,
The automatic control device is configured to inject a predetermined amount of oil in an oil tank into a treatment kiln;
An oil heating controller that gradually heats the oil in the treatment kettle from room temperature to 120 ° C. in 2 hours, and further gradually heats to 240 ° C. below the ignition point of the wood in 2 hours by the boiler;
An oil transfer control unit for introducing heated oil in the processing kiln into the radiator from the processing kiln;
When the oil in the radiator is cooled to a predetermined temperature, the oil recovery control unit returns the oil from the heater to the oil tank via the pump.
In the invention of the oil penetration / drying method of claim 3,
The treatment furnace is filled with oil such as vegetable oil and gradually heated from room temperature to the temperature at which free water evaporates with a boiler, and further heated gradually to a temperature below the ignition point of wood with a boiler. The wood is dried through a second heating step in which the water content of the wood is vaporized to reduce the moisture content of the wood to 10% or less, and the oil that has heated the drying time in the treatment furnace by the boiler reaches the core of the wood. It is characterized in that the time for impregnation on the surface side is set without impregnation.
In the invention of claim 4,
The first drying step is a stepwise heating from room temperature to 120 ° C. in 2 hours,
The second drying step is characterized by heating stepwise to 240 ° C. below the ignition point of wood in 2 hours.

The oil permeation / drying apparatus of the present invention is heated to a high temperature by filling the treatment kiln with oil such as vegetable oil and gradually heating it in a relatively short time to raise the temperature of the oil to below the ignition point of the wood. The obtained oil is shallowly permeated to the surface of the wood without penetrating the core of the wood, and at the same time, moisture in the wood is vaporized to lower the water content to 10% or less.
That is, the wood contains free water and bound water, and the free water enters the gaps between the cells of the wood, but the bound water is a cellulose in the cell wall, such as cellulose, lignin, polysaccharides, etc. It is crystallized by chemical bonding with the hydrophilic hydroxyl group.
Therefore, free water of wood can be vaporized from the inside by natural drying by solar heat or heating at about 120 ° C, but the bound water is included in the amorphous state by further gradually increasing the temperature. Water can be vaporized and the water content can be reduced to 10% or less.
As a result, cellulose, lignin, polysaccharides, etc., change into a lump when the wood returns to room temperature, and the degree of shrinkage of the wood is less than one-tenth that of conventional intermediate dry wood (water content of about 15%). It turned out that there was almost no change.
And the strength measurement value of the wood after such a high temperature drying process increases bending strength and compressive strength.
In addition, oil that has been impregnated with oil and dried (sheets and squares) adheres with oil that has penetrated within a depth of 2 to 3 mm from the surface, preventing the wood from shrinking too much while maintaining its anti-corrosion and insect-proofing effects. Therefore, it is excellent in convenience and suitable for wet edges and outdoor use.
Moreover, when it is not necessary to attach the oil, it can be scraped off by pre-cutting.

It is a block diagram which shows the Example of an oil osmosis | permeation / drying apparatus. It is the flowchart which showed the control procedure of the automatic control apparatus of an oil osmosis | permeation / drying apparatus.

In the same treatment kiln, the wood is dried with heated oil to a moisture content of 10% or less, and at the same time, oil such as vegetable oil is allowed to penetrate the surface of the wood, thereby reducing the degree of shrinkage of the wood. Provided with oil-impregnated / dried wood that is resistant to corrosion and has excellent insect repellent properties, and is also suitable for wet edges and outdoor applications.
Hereinafter, embodiments of an oil permeation / drying apparatus using vegetable oil as oil will be described with reference to the drawings.

[Oil penetration / drying equipment]
As shown in FIG. 1, the oil permeation / drying apparatus 1 stores an oil tank 2 filled with vegetable oil and a processing wood (plate material / square material) W and injects the vegetable oil from the oil tank 2. A drying treatment furnace 3, a heat medium boiler 4 for heating the vegetable oil filled in the drying treatment vessel 3, a radiator 5 installed in water for introducing the heated vegetable oil from the treatment vessel 3, and the radiator 5 When the vegetable oil is lowered to a predetermined temperature, the pump 6 is returned to the oil tank 2 and an automatic controller 10 for controlling them.

[Oil tank]
The oil tank 2 is filled with vegetable oil as oil for drying and impregnating wood.
The oil tank 2 has an on-off valve (not shown), and is connected to the inlet of the processing kettle 3 through a pipe L1.
The vegetable oil may be fresh vegetable oil or used vegetable oil.
In this invention, it is not limited to vegetable oil, Other oil may be used and waste oil may be sufficient.

[Drying kiln]
In the case of the present embodiment, the drying treatment kiln 3 has a closed cylindrical shape having a heater H that heats the inside of the drying kiln by the heat medium boiler 4, and is provided with an open / close door 3A for storing wood on one side. ing.
Moreover, it has the injection port 31 which inject | pours vegetable oil from the said oil tank 2 via the piping L1, and the discharge port 32 for making high temperature vegetable oil flow out to the below-mentioned heat radiator 5 after a drying process.

[Heat medium boiler]
The heating medium boiler 4 is a known heating medium boiler that heats the heater H of the drying treatment furnace 3, and controls the heating temperature of the vegetable oil in the drying treatment furnace 3 under the control of an automatic control device 10 described later. Yes.
In the present embodiment, the heating in the drying furnace 3 is performed by heating the heater H with the heat medium boiler 4, but the structure of the heater is not particularly limited to the illustrated example, and other electric heaters that do not use the heat medium boiler are known. The heater structure may be used.

[Heatsink]
The radiator 5 includes a radiator that performs heat exchange. In the case of the present embodiment, the radiator 5 has a water-cooled structure that is submerged in natural water such as a river or water such as a water tank or a pool. Yes.
The radiator 5 is connected to the outlet 32 of the drying furnace 3 via a pipe L2. After the drying treatment by the drying furnace 3, the heated vegetable oil in the drying furnace 3 is quickly dried. The vegetable oil discharged from the kiln 3 is prevented from being impregnated to the core of the wood W.

[pump]
The radiator 5 is provided with a temperature sensor S for detecting the temperature of the radiated vegetable oil. When the detected value of the temperature sensor S reaches a certain temperature, the pump 6 is operated to reduce the temperature. The vegetable oil is returned from the radiator 5 to the oil tank 2 via the pipe line L3.

[Automatic control device]
In the present embodiment, the above processing is automatically operated by the automatic control device 10.
When the wood W is carried into the drying furnace 3 and the open / close door 3A is closed and sealed, the operator turns on a process start switch on a control panel (not shown).
Thereby, a predetermined amount of vegetable oil is filled from the oil tank 2 into the drying treatment kiln 3 via the pipe L1.

Next, the heating medium boiler 4 heats the vegetable oil via the heater H in the drying treatment furnace 3.
During the heating, the automatic control device 10 performs a first drying process in which the oil temperature is gradually heated from room temperature to 120 ° C. in about 2 hours (first drying step).
The reason why the temperature is set to 120 ° C. is that the free water of the wood can be vaporized out of the wood by natural drying from solar wood or heating at about 120 ° C.
The heating is performed, for example, by + 10 ° C.
Thereby, the free water in the timber W can be vaporized out of the timber.

Similarly, the automatic control apparatus 10 performs a second drying process in which heating is performed gradually from 120 ° C. to 240 ° C. in about 2 hours (second drying step).
The upper limit is set to 240 ° C. The flash point of vegetable oil, for example, rapeseed oil, is 313 to 320 ° C., and the ignition point of wood is 250 to 260 ° C. (Japan Oil Inspection 1983, Chemical substance risk prediction data -Since the Research Center for Measures (1984), it was set to 240 ° C in consideration of safety, but it may exceed 240 ° C if it is below the ignition point of vegetable oil and wood.
And when oil temperature exceeds about 200 degreeC, the water | moisture content (bonded water) contained in the amorphous state of wood vaporizes and is expelled outside.
Thereby, the moisture content of wood can be made 10% or less.

When the bound water in the wood is vaporized in this way, the polysaccharides such as cellulose and lignin become lumps when they return to room temperature, so the degree of shrinkage of the wood is one-tenth that of a conventional desiccant with a high moisture content. It was confirmed that the shrinkage change was very small.
As described above, the wood W can be dried to a moisture content of 10% or less by the drying furnace 3, and the vegetable oil can be impregnated only on the surface side without impregnating the core of the wood W.

When the drying / impregnation process is finished, the heating medium boiler 4 is stopped, the discharge port of the drying furnace 3 is opened, and the heated vegetable oil in the drying furnace 3 is put into the radiator 5 through the pipe L2. The heat is exchanged by the radiator 5.
In this embodiment, the radiator 5 is made of a radiator submerged in water such as a river, a pool, or a water tank, filled with vegetable oil whose upper limit is 240 ° C., and water-cooled.
When the cooled temperature reaches a set value of 40 to 50 ° C., the sensor S provided in the radiator 5 detects the set value, and the automatic control device 10 that has received the detection signal receives a pump (pump pump, etc.) 6 Is operated to return the low-temperature vegetable oil to the oil tank 2 from the radiator 5 via the pipe L3, and the automatic control cycle is completed.

Comparison of moisture content due to differences in drying methods (average moisture content for each tree species of desiccant under conditions of air temperature 20 ° C and humidity 76%)
(1) Natural drying (drying by the sun)
Tree species Moisture content Ezo pine 14.72
Sugi 14.57
Fir 14.43
Akamatsu 14.19
Tsuga 14.17
Mizunara 14.00
(2) Drying using water vapor Tree species Moisture content Ezo pine 13.43
Sugi 12.39
Fir 12.35
Akamatsu 13.13
Tsuga 12.45
Mizunara 12.25
(3) Dried tree species according to this example Moisture content Ezo pine 9.52
Sugi 8.28
Fir 8.26
Red Pine 9.63
Tsuga 8.91
Mizunara 8.67
It was confirmed that the moisture content was 10 or less by the treatment of this example.

Comparison of freshly milled dimensions considering shrinkage due to drying Published dimensions For natural and steam drying For this example 45 mm 46.4 mm 45.0 mm
75mm 77.4mm 75.0mm
105mm 108.4mm 105.0mm
120mm 123.8mm 120.0mm
210mm 216.7mm 210.0mm
It was confirmed that there was almost no expansion and contraction when the water content was 10% or less.
The present invention is not limited to the above-described embodiment. In short, various design changes can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Oil osmosis | permeation / drying apparatus 2 Oil tank 3 Processing kiln 4 Heating medium boiler 5 Radiator 6 Pump 10 Automatic control apparatus

Claims (4)

An oil tank filled with oil for drying and impregnating wood such as vegetable oil;
A processing kiln that stores wood and injects oil from the oil tank into the interior,
A boiler that is heated and controlled at a time and a temperature at which the oil in the treatment kettle is gradually heated so that the moisture content of the wood is 10% or less and the oil does not impregnate the core of the wood but only impregnation on the front edge side;
A radiator that flows and cools the heated oil in the treatment kiln from the treatment kettle through a pipeline;
A pump for returning to the oil tank when the oil is reduced to a predetermined temperature by the radiator;
An oil permeation / drying device comprising an automatic control device for controlling the temperature of oil in the treatment furnace by heating control of a boiler. An automatic injection device that injects a predetermined amount of oil in the oil tank into the treatment kiln;
An oil heating control unit that gradually heats the oil in the treatment kettle from room temperature to 120 ° C. in 2 hours by a boiler, and further gradually heats to a high temperature that does not exceed the ignition point of oil and wood in 2 hours by the boiler;
An oil transfer control unit for introducing heated oil in the processing kiln into the radiator from the processing kiln;
2. The oil permeation / drying device according to claim 1, further comprising an oil recovery control unit that returns the oil in the radiator to an oil tank through a pump when the oil is cooled to a predetermined temperature. In the oil penetration / drying method using the oil penetration / drying device according to claim 1,
Fill the treatment kiln with oil such as vegetable oil, and gradually heat it from room temperature to the temperature at which free water evaporates with a boiler, and then gradually heat to a high temperature that does not exceed the ignition point of oil and wood with a boiler. Then, the wood is dried through the second heating step of evaporating the bound water in the wood to reduce the moisture content of the wood to 10% or less, and the oil heated for the drying time in the treatment furnace by the boiler is wood. An oil permeation / drying method characterized in that it is set to a time for impregnation on the surface side without impregnating the core. The first drying step is a stepwise heating from room temperature to 120 ° C. in 2 hours,
The oil penetration / drying method according to claim 3, wherein the second drying step is stepwise heated in 2 hours to 240 ° C below the ignition point of wood.

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